Which Blood Tests Detect Diabetes? Fasting Glucose and HbA1c
Right now, all the blood in your body carries about four or five grams of sugar, roughly a teaspoon. Here we explain how your body keeps it at that level, which two numbers on a blood test reveal diabetes before you notice anything, and which two habits slow it down more effectively than a drug.
How the Body Controls Blood Sugar
Glucose is the fuel your cells run on. To get into them, it needs a key: insulin, which is made by the pancreas.
When you eat, the pancreas releases insulin and your blood glucose falls. When you are fasting, another hormone, glucagon, takes over and releases sugar from the liver. If the key stops working, sugar builds up in the blood. That is diabetes.
Types of Diabetes: Type 1, Type 2 and Gestational
In type 1 diabetes, the immune system destroys the cells that make insulin. It is not caused by eating sweets.
Type 2 accounts for around 90% of cases. It works like a jammed lock: there is insulin, but the cells respond poorly to it.
Gestational diabetes develops during pregnancy. Screening for it takes place between weeks 24 and 28.
Why Type 2 Diabetes Often Goes Unnoticed
Type 2 diabetes can go for years without any signs. Meanwhile, high blood sugar gradually damages the eyes, kidneys, nerves and heart. In Spain, according to the di@bet.es study, nearly half of the people who had it did not know.
When it does cause symptoms, the most common are intense thirst, needing to urinate often, blurred vision and unintentional weight loss. If you notice any of these, make an appointment with your doctor.
The Two Test Results That Reveal Diabetes
The first is fasting glucose. Below 100 mg/dl is normal. Between 100 and 125 mg/dl indicates prediabetes. From 126 mg/dl upward, confirmed in two tests, it is considered diabetes.
The second is glycated hemoglobin (HbA1c). Glucose sticks to the hemoglobin in red blood cells, which live for about four months. That is why this test does not measure today's sugar level but the average over the past two or three months. Fasting the night before does not change the result.
Its reference ranges are as follows: below 5.7%, normal; between 5.7% and 6.4%, prediabetes; 6.5% or above, diabetes.
Two Habits That Slow Prediabetes
The first is getting at least 150 minutes of physical activity a week. Working muscles use up glucose and respond better to insulin. One option is brisk walking for 30 minutes five days a week, at a pace where you can talk but not sing.
The second, if you are overweight, is losing around 7% of your body weight, because abdominal fat worsens the body's response to insulin. At 90 kilos, that is about six. Swapping soft drinks and juices for water and filling half your plate with vegetables both help.
More Effective Than a Drug
The Diabetes Prevention Program was a 2002 US trial involving people with prediabetes who were overweight. Combining both habits reduced the onset of type 2 diabetes by 58%.
Metformin, the drug it was compared with, reduced it by 31%. The glucose in your blood changes every hour, but glycated hemoglobin reflects what has happened over the past three months.
Frequently asked questions
What is a normal fasting blood glucose level?
Below 100 mg/dl is normal. Between 100 and 125 indicates prediabetes, and from 126 upward, confirmed in two tests, diabetes.
Do you need to fast before an HbA1c test?
Fasting the night before does not change the result, because the test measures your average blood sugar over the past two or three months.
What symptoms can diabetes cause?
Intense thirst, needing to urinate often, blurred vision or unintentional weight loss. Type 2 diabetes, however, can go for years without any signs.
Does eating sweets cause type 1 diabetes?
No. In type 1 diabetes, the immune system destroys the cells in the pancreas that make insulin.
Informative article written with the help of AI tools from the verified script of the video. The video is in Spanish.